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991.
Gate control characteristics of GaAs-based quantum wire transistors (QWRTrs) controlled by a nanometer-scale Schottky wrap gate (WPG) are investigated theoretically and experimentally. Gate bias dependence of the effective wire width of fabricated WPG QWRTrs determined theoretically as well as experimentally from Landau plots showed that the nanometer-scale WPG controls the potential very tightly near channel pinch-off and that the pinch-off threshold voltage is strongly dependent on the gate length, LG, when LG is shorter than 400 nm. The theory based on the three-dimensional (3D) potential simulation pointed out that Fermi level pinning on the semiconductor surface around the WPGs strongly affects the gate controllability in the nanometer-scale Schottky WPG structure. 相似文献
992.
均匀磁场中的二维氢原子 总被引:1,自引:0,他引:1
研究了二维氢原子在均匀磁场中的结构问题,随着磁场增强,能级出现分裂交叉和聚束的现象。 相似文献
993.
New NCP-Functions and Their Properties 总被引:7,自引:0,他引:7
Kanzow C. Yamashita N. Fukushima M. 《Journal of Optimization Theory and Applications》1997,94(1):115-135
Recently, Luo and Tseng proposed a class of merit functions for the nonlinear complementarity problem (NCP) and showed that it enjoys several interesting properties under some assumptions. In this paper, adopting a similar idea to that of Luo and Tseng, we present new merit functions for the NCP, which can be decomposed into component functions. We show that these merit functions not only share many properties with the one proposed by Luo and Tseng but also enjoy additional favorable properties owing to their decomposable structure. In particular, we present fairly mild conditions under which these merit functions have bounded level sets. 相似文献
994.
本文用统计学中的假设检验方法对司法审判中的定罪过程作一个比较分析,从另外一个角度来理解司法公正的内涵。 相似文献
995.
N. Nguyen A. Ducouret F. Studer V. Aubin D. Caurant D. Gourier J.-M. Costantini 《Hyperfine Interactions》2005,166(1-4):489-493
Several single phase hollandite ceramics having Ba2+ x Cs+ y (C = Al,Fe)3+ 2x+y Ti4+ 8?2x?y O16 composition have been synthesized and irradiated under external electron beams simulating the β-irradiation of radioactive cesium. These samples have been characterized by 57Fe transmission Mössbauer spectroscopy. Mössbauer results show that the irradiation modifies the local arrangements of Ba cations around Fe3+ ions by atomic displacement of Ba ions. 相似文献
996.
基于SystemC的事务级AMBA总线模型的设计与实现 总被引:6,自引:1,他引:5
针对目前SoC设计中的时间瓶颈,根据系统建模语言SystemC对SoC进行事务级建模的方法。提出并实现了采用该方法构建基于AMBA规范的SoC片内总线模型的方案.模型采用了SystemC 2.0的接口、端口和通道的概念,这使模型具有很好的开放性和可扩展性.模型各部分间的通信通过调用各接口内定义的函数来进行,模型运行时只使用SystemC自带的轻量级仿真内核.实验结果表明:本总线模型完全符合AMBA2.0规范,可以有效克服目前SoC软硬件协同设计中的时间瓶颈. 相似文献
997.
一类半鞅样本轨道的Fractal性质 总被引:2,自引:0,他引:2
本文用Hausdorff维数刻画了一类半这样本轨道的Fractal性质,并由此研究了Brown运动与有界变差过程的碰撞问题. 相似文献
998.
J. Ferrera 《Transactions of the American Mathematical Society》1998,350(12):4757-4773
In this paper we give a characterization of pointwise and uniform convergence of sequences of homogeneous polynomials on a Banach space by means of the convergence of their level sets. Results are obtained both in the real and the complex cases, as well as some generalizations to the nonhomogeneous case and to holomorphic functions in the complex case. Kuratowski convergence of closed sets is used in order to characterize pointwise convergence. We require uniform convergence of the distance function to get uniform convergence of the sequence of polynomials.
999.
1000.
222Rn concentrations in the air in one sampling point located in Nerja Cave (Spain) () have been measured over one year, since July 2003–June 2004. 222Rn levels were continuously monitored using Alpha-Guard (Genitron instruments) equipment, model PQ2000PRO. Firstly, the aim of this study was to perceive the daily, monthly and seasonal variations patterns of 222Rn concentrations. Diurnal cycles are presented by season showing that the 222Rn concentrations in spring–summer are higher than autumn–winter. The hourly variations are discussed in relation to various meteorological factors measured in the Cave and also on the outdoor. We have evaluated the radiation exposure levels for workers and tourists; those represent only a low percentage of the exposure guides for the general population ICRP, 1994. Protection against Radon-222 at home and at work. Pergamon Press, Oxford (publication 65). 相似文献